#include <QtGui>

#include "TreeItem.h"
#include "TreeModel.h"

TreeModel::TreeModel(const QString &data, QObject *parent) : QAbstractItemModel(parent)
{
  QList<QVariant> rootData;
  rootData << "PID" << "Name";
  rootItem = new TreeItem(rootData);
  setupModelData(data.split(QString("\n")), rootItem);
}

TreeModel::~TreeModel()
{
  delete rootItem;
}

int TreeModel::columnCount(const QModelIndex &parent) const
{
  if (parent.isValid())
    return static_cast<TreeItem*>(parent.internalPointer())->columnCount();
  else
    return rootItem->columnCount();
}

QVariant TreeModel::data(const QModelIndex &index, int role) const
{
  if (!index.isValid())
    return QVariant();

  if (role != Qt::DisplayRole)
    return QVariant();

  TreeItem *item = static_cast<TreeItem*>(index.internalPointer());

  return item->data(index.column());
}

Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const
{
  if (!index.isValid())
    return 0;

  return Qt::ItemIsEnabled | Qt::ItemIsSelectable;
}

QVariant TreeModel::headerData(int section, Qt::Orientation orientation,
			       int role) const
{
  if (orientation == Qt::Horizontal && role == Qt::DisplayRole)
    return rootItem->data(section);

  return QVariant();
}

QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent)
  const
{
  if (!hasIndex(row, column, parent))
    return QModelIndex();

  TreeItem *parentItem;

  if (!parent.isValid())
    parentItem = rootItem;
  else
    parentItem = static_cast<TreeItem*>(parent.internalPointer());

  TreeItem *childItem = parentItem->child(row);
  if (childItem)
    return createIndex(row, column, childItem);
  else
    return QModelIndex();
}

QModelIndex TreeModel::parent(const QModelIndex &index) const
{
  if (!index.isValid())
  {
    return QModelIndex();
  }

  TreeItem *childItem = static_cast<TreeItem*>(index.internalPointer());
  TreeItem *parentItem = childItem->parent();

  if (parentItem == rootItem)
  {
    return QModelIndex();
  }

  return createIndex(parentItem->row(), 0, parentItem);
}

int TreeModel::rowCount(const QModelIndex &parent) const
{
  TreeItem *parentItem;
  if (parent.column() > 0)
    return 0;

  if (!parent.isValid())
  {
    parentItem = rootItem;
  }
  else
  {
    parentItem = static_cast<TreeItem*>(parent.internalPointer());
  }

  return parentItem->childCount();
}

// TODO : This all need to be replaced to read directly from the Process list
void TreeModel::setupModelData(const QStringList &lines, TreeItem *parent)
{
  QList<TreeItem*> parents;
  QList<int> indentations;
  parents << parent;
  indentations << 0;

  int number = 0;

  while (number < lines.count()) 
  {
    int position = 0;
    while (position < lines[number].length()) 
    {
      if (lines[number].mid(position, 1) != " ")
      {
	break;
      }
      position++;
    }

    QString lineData = lines[number].mid(position).trimmed();

    if (!lineData.isEmpty()) 
    {
      // Read the column data from the rest of the line.
      QStringList columnStrings = lineData.split("\t", QString::SkipEmptyParts);
      QList<QVariant> columnData;
      for (int column = 0; column < columnStrings.count(); ++column)
	columnData << columnStrings[column];

      if (position > indentations.last()) {
	// The last child of the current parent is now the new parent
	// unless the current parent has no children.

	if (parents.last()->childCount() > 0) {
	  parents << parents.last()->child(parents.last()->childCount()-1);
	  indentations << position;
	}
      } 
      else 
      {
	while (position < indentations.last() && parents.count() > 0) 
	{
	  parents.pop_back();
	  indentations.pop_back();
	}
      }

      // Append a new item to the current parent's list of children.
      parents.last()->appendChild(new TreeItem(columnData, parents.last()));
    }

    number++;
  }
}

